Cup-shaped chuck of substrate holding device and substrate holding device

ABSTRACT

A cup-shaped chuck of a substrate holding device includes an inner pressing ring, a middle frame, a sealing element, an outer pressing ring and a contact ring. The inner pressing ring is locked on the inner peripheral surface of the middle frame. The sealing element has an outer end part, a bottom part and an inner end part. The outer end part of the sealing element wraps the outer peripheral surface of at least part of the middle frame. The bottom part of the sealing element wraps the bottom of the middle frame, and is exposed to the outside of the cup-shaped chuck. The inner end part of the sealing element wraps the inner peripheral surface of at least part of the middle frame and is pressed between the inner pressing ring and the middle frame by the inner pressing ring.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to the technical field of semiconductorelectroplating, and more particularly, to a cup-shaped chuck for holdinga substrate during electroplating and a substrate holding device.

2. The Related Art

An electroplating chuck that holds a substrate is an important part of asemiconductor electroplating equipment. The electroplating chuck isusually equipped with a contact ring and a sealing element, and thesealing element is used to isolate the electroplating solution from thecontact ring, so as to avoid the uneven electroplating film caused bypoor contact between the contact ring and the seed layer. Therefore, theperformance of the sealing element is a key factor in ensuring thenormal operation of the electroplating process.

At present, there are still many problems in the long-term use of thesealing element in the electroplating chuck. For example: 1) As shown inFIG. 18 , the electroplating chuck adopts all-wrapped type sealingelement 23, and the exposed area of the sealing element 23 is too large,so the outer side 231 and the bottom surface 233 of the sealing element23 are easily damaged, and especially the bottom bending part 232 iseasily damaged. Once the sealing element 23 is damaged, the penetrationof the electroplating solution through the sealing element 23 and thecontact with the internal metal base 22 will result in partial loss ofcurrent, so that the thickness of the electroplating layer on thesubstrate is lower than the predetermined target value, which affectsthe product yield. 2) The sealing element 23 wraps a relatively hardmetal base 22. The bottom of the metal base 22 is bent upward to form asupport part 221, and the thickness of the support part 221 is only 1mm, which is very sharp. The sealing element 23 wraps the support part221 to form a sealing lip part 234. During the electroplating process,the sealing lip part 234 is in close contact with the substrate throughpressure to achieve sealing at the edge and the back of the substrate.However, prolonged stress on the sealing lip part 234 can easily causethe sealing lip part 234 to age and crack. 3) When the electroplatingchuck is maintained, the contact ring 25 and the sealing element 23 needto be cleaned. However, the inner pressure ring 24 and the contact ring25 of the existing electroplating chuck are directly conductive, andthere is no seal between the outer metal base 22. When using an onlinespray cleaning or immersion cleaning, the cleaning solution orelectroplating solution will penetrate into the inner layer of theelectroplating chuck along the arrow shown in FIG. 18 , which cannotachieve the purpose of rapid cleaning and maintenance. It needs to bedisassembled separately for maintenance.

SUMMARY

One purpose of the present invention is to provide a cup-shaped chuck ofa substrate holding device, which can effectively reduce the risk ofdamage of the sealing element by reducing the exposed area of thesealing element, and in addition, by improving the installation sealingperformance of the contact ring, online cleaning of the contact ring andthe sealing element can be achieved.

In order to achieve the above purpose, the cup-shaped chuck of thesubstrate holding device provided by the present invention includes acup-shaped chuck for holding a substrate, and the cup-shaped chuckincludes:

-   -   an inner pressure ring;    -   a middle frame, the inner pressure ring being locked on the        inner peripheral surface of the middle frame;    -   a sealing element, the sealing element having an outer end part,        a bottom part and an inner end part, the outer end part of the        sealing element wrapping the outer peripheral surface of at        least part of the middle frame, the bottom part of the sealing        element wrapping the bottom of the middle frame and being        exposed to the outside of the cup-shaped chuck, the inner end        part of the sealing element wrapping the inner peripheral        surface of at least part of the middle frame, the inner end part        of the sealing element being pressed between the inner pressure        ring and the middle frame by the inner pressure ring;    -   an outer pressure ring, the outer pressure ring being made of        insulating material and locked on the outer peripheral surface        of the middle frame, the outer end part of the sealing element        being pressed between the outer pressure ring and the middle        frame through the outer pressure ring; and    -   a contact ring, the contact ring being located above the sealing        element and pressed between the inner pressure ring and the        middle frame, and a sealing ring being disposed between the        inner pressure ring and the contact ring.

By employing an insulating outer pressure ring, and is locked with thesealing element, and only the bottom part of the sealing element isexposed, which is beneficial to reduce the exposed area of the sealingelement and the risk of damage. By setting the sealing ring between theinner pressure ring and the middle frame, which is beneficial to improvethe overall sealing of the cup-shaped chuck, preventing theelectroplating solution or cleaning solution from penetrating into theinner layer of the cup-shaped chuck.

Preferably, in the cup-shaped chuck of the substrate holding device, thebottom of the middle frame forms a horizontal support part radially andhorizontally inward, and the bottom part of the sealing element wrapsthe horizontal support part. The end of the horizontal support partprotrudes upwards to form a sealing lip part, and the number of sealinglip parts is one or two or more, and the sealing lip part is configuredfor sealing contact with the edge of the substrate.

There is no hard material support inside the sealing lip part, so as toavoid the inner hard support damaging the sealing lip part when thesealing lip part is pressed, which can prolong the service life of thesealing element. At the same time, the radial width of sealing lip partcan be designed to be less than 1 mm to meet the subsequent narroweredge removal process requirements. When two or more sealing lip partsare provided, multi-stage sealings can be formed between the sealingelement and the edge of the substrate, so as to achieve better sealingeffect.

Preferably, in the cup-shaped chuck of a substrate holding device, whenthe number of sealing lip parts is two or more, the heights of the twoor more sealing lip parts are the same.

Preferably, in the cup-shaped chuck of a substrate holding device, whenthe number of sealing lip parts is two or more, there is a heightdifference between at least two of the sealing lip parts.

Preferably, in the cup-shaped chuck of a substrate holding device, theheight of the sealing lip parts gradually increases radially inward.

Preferably, in the cup-shaped chuck of a substrate holding device, theheight of the sealing lip parts gradually decreases radially inward.

Preferably, in the cup-shaped chuck of a substrate holding device, theheights of the sealing lip parts are alternately arranged high and lowin the radial direction.

Preferably, in the cup-shaped chuck of a substrate holding device, whenthere is one sealing lip part, the radial width of the one sealing lippart is not more than 1 mm, and when there are two or more sealing lipparts, the total radial width of the two or more sealing lip parts isnot more than 1 mm.

Preferably, in the cup-shaped chuck of a substrate holding device, whenthere is one sealing lip part, the radial width of the one sealing lippart is 0.4 mm-0.8 mm, and when the number of sealing lip parts is twoor more, the total radial width of the two or more sealing lip parts is0.4 mm-0.8 mm.

Preferably, in the cup-shaped chuck of a substrate holding device, thesealing element as a separate accessory is detachable from the middleframe.

Preferably, in the cup-shaped chuck of a substrate holding device, thesealing element is bonded to the middle frame by an adhesive.

Preferably, in the cup-shaped chuck of a substrate holding device,several inner sealing protrusions are formed on the contact surface ofthe sealing element and the middle frame, and correspondingly, thesurface of the middle frame has several sealing grooves that match theinner sealing protrusions.

The inner sealing protrusions can form multi-stage sealings between thesealing element and the middle frame. Once a certain part of the sealingelements damaged, the multi-stage sealings can reduce the diffusion ofthe electroplating solution into the inner layer of the cup-shaped chuckand reduce the impact of the electroplating solution on the devicecorrosion.

Preferably, in the cup-shaped chuck of a substrate holding device,several outer sealing protrusions are formed on the contact surface ofthe sealing element and the outer pressure ring.

The outer sealing protrusions can enhance the sealing between the outerpressure ring, the middle frame and the sealing element. In addition,the inner sealing protrusions and the outer sealing protrusions are alsoconducive to the positioning of the sealing element and the middle frameduring assembly, making the assembly of the two components more precise.

Preferably, in the cup-shaped chuck of a substrate holding device, thesealing element has hydrophobicity properties.

The hydrophobic treatment of the sealing element can reduce the adhesionof liquid on its surface. The hydrophobic treatment of the sealingelement can use hydrophobic materials, or doped hydrophobic materials,or surface coating or sputtering hydrophobic films, or reducing surfaceroughness. Preferably, the surface roughness Ra of the sealing elementis less than 10 nm.

Preferably, in the cup-shaped chuck of a substrate holding device, theouter surface of the outer pressure ring has a blocking part.

By forming the blocking part on the outer surface of the outer pressurering, it can increase the resistance of the liquid to climb upward alongthe outer surface of the outer pressure ring, guide the liquid to changeits flow direction and make the liquid be thrown obliquely downward intothe liquid collection trough arranged in the electroplating chamber,thereby preventing the liquid from being thrown out of theelectroplating chamber and polluting the process environment.

Preferably, in the cup-shaped chuck of a substrate holding device, theblocking part comprises at least an upper blocking part and/or a lowerblocking part. The number of upper blocking parts is one or more, andthe number of lower blocking parts is one or more. The upper blockingpart is a downward annular protrusion formed on the top of the outerpressure ring, and the lower blocking part is an outward annularprotrusion formed at the middle and lower part of the outer pressurering.

Preferably, in the cup-shaped chuck of a substrate holding device, thesurface of the outer pressure ring has hydrophobicity properties.

The hydrophobic treatment of the outer pressure ring can reduce theadhesion of liquid on its surface. Specifically, the outer pressure ringcan be made of hydrophobic materials, or doped hydrophobic materials, ora hydrophobic film is formed on the surface of the outer pressure ring,or the surface roughness Ra of the outer pressure ring is less than 10nm.

Preferably, in the cup-shaped chuck of a substrate holding device,several bumps are formed on the contact surface of the outer pressurering and the sealing element, and several bumps are formed on thecontact surface of the inner pressure ring and the sealing element.

The bumps on the contact surfaces of the outer pressure ring and theinner pressure ring and the sealing element can improve the sealingeffect between the parts in contact with each other.

Preferably, in the cup-shaped chuck of a substrate holding device, thebottom of the outer pressure ring has several bumps.

Several bumps set at the bottom of the outer pressure ring can play asupporting role during the maintenance of the device, it can keep thesealing element and the worktable at a certain distance, and reduce thedamage or contamination of the sealing element.

Preferably, in the cup-shaped chuck of a substrate holding device, thematerial of the inner pressure ring is a conductive andcorrosion-resistant metal, and the contact ring is electricallyconnected to the electroplating power supply through the inner pressurering.

Preferably, in the cup-shaped chuck of a substrate holding device, theinner pressure ring is made of insulating material, and the middle frameis made of conductive metal, and the contact ring is electricallyconnected to the electroplating power supply through the middle frame.

Employing the middle frame to electrically connect the contact ring andthe electroplating power supply, the inner pressure ring does not needto meet both conductivity and corrosion resistance, but only needs tohave corrosion resistance, that is, the inner pressure ring can be madeof insulating materials (such as PVC, PTFE, PVDF, etc.), thus, thematerial selection range of the inner pressure ring is expanded, whichis beneficial to reduce the cost and realize the on-line cleaning of thecup-shaped chuck.

In the present invention, a substrate holding device is also provided,comprising:

-   -   the cup-shaped chuck of any of the above, for holding a        substrate;    -   a chuck plate, the chuck plate pressing against the backside of        the substrate so that the substrate is in pressing contact with        the sealing element of the cup-shaped chuck;    -   a chuck plate driving device configured for driving the chuck        plate against or away from the backside of the substrate;    -   an angle driving device configured for adjusting the angle of        the substrate clamped by the cup-shaped chuck and the chuck        plate;    -   a rotation driving device configured for driving the substrate        clamped by the cup-shaped chuck and the chuck plate to rotate;        and    -   a vertical driving device configured for driving the substrate        clamped by the cup-shaped chuck and the chuck plate to ascend or        descend.

Preferably, in the substrate holding device, the chuck plate comprises abase. The base has a lower surface in contact with the backside of thesubstrate. The lower surface has several exhaust grooves, and theperiphery of the base has several exhaust holes communicating with theexhaust grooves.

The exhaust grooves and the exhaust holes on the chuck plate facilitatethe separation of the chuck plate and the substrate when the substrateis unloaded.

Preferably, in the substrate holding device, the lower surface of thebase has contact parts protruding toward the substrate, so as to reducethe contact area between the chuck plate and the substrate.

The cup-shaped chuck of a substrate holding device of the presentinvention adopts an insulating outer pressure ring, which is lockedtightly with the middle frame wrapped by the sealing element, so thatonly the bottom part of the sealing element is exposed, which greatlyreduces the exposed area of the sealing element in the electroplatingsolution, and thus reduces the risk of damage of the sealing element andimproves the reliability of the operation of the device; besides, thesealing ring is disposed between the inner pressure ring and the contactring, so that the upper and lower sides of the contact ring are reliablysealed. During the maintenance of the device, especially when cleaningthe contact ring and the sealing element, it can effectively preventprocess liquids from infiltrating the inner layer of the cup-shapedchuck, and it is not necessary to disassemble and then maintain eachpart one by one, which can realize online cleaning, improving theconvenience and the efficiency of the device maintenance, and reducingmaintenance costs.

BRIEF DESCRIPTION OF THE DRAWINGS

The features and performance of the present invention are furtherdescribed by the following embodiments and accompanying drawings.

FIG. 1 illustrates a perspective view of a substrate holding device ofthe present invention;

FIG. 2 illustrates another perspective view of the substrate holdingdevice of the present invention;

FIG. 3 illustrates a cross-sectional view of the substrate holdingdevice of the present invention;

FIG. 4 illustrates another cross-sectional view of the substrate holdingdevice of the present invention;

FIG. 5 illustrates a partial enlarged view of A portion in FIG. 4 ;

FIG. 6 illustrates an enlarged view of some of the components in FIG. 5;

FIG. 7 illustrates a perspective view of a cup-shaped chuck of thepresent invention;

FIG. 8 illustrates an exploded view of the cup-shaped chuck of thepresent invention;

FIG. 9 illustrates a partial cross-sectional view of a middle frame ofthe present invention;

FIG. 10 illustrates a partial cross-sectional view of a sealing elementof the present invention;

FIG. 11 illustrates a perspective view of an outer pressure ring of thepresent invention;

FIG. 12 illustrates a perspective view of a chuck plate of the presentinvention;

FIG. 13 illustrates another perspective view of the chuck plate of thepresent invention;

FIG. 14 illustrates a cross-sectional view of the chuck plate of thepresent invention;

FIG. 15 illustrates a partial enlarged view of B portion in FIG. 14 ;

FIGS. 16 a to 16 d illustrate schematic views of different forms ofouter pressure rings;

FIGS. 17 a to 17 c illustrate partial schematic views of different formsof sealing elements; and

FIG. 18 illustrates an enlarged view of some components of an existingelectroplating chuck.

DETAILED DESCRIPTION OF EMBODIMENTS

In order to describe the technical content, structural features,objectives and effects of the present invention in detail, the followingwill be described in detail with reference to embodiments and drawings.

FIGS. 1 and 2 illustrate a substrate holding device in an embodiment ofthe present invention. The substrate holding device includes componentssuch as a cup-shaped chuck 11, a chuck plate 12, a chuck plate drivingdevice 13, an angle driving device 14, a rotation driving device 16, anda vertical driving device. An accommodating space 110 is formed at thecenter of the cup-shaped chuck 11, and the accommodating space 110 isused for accommodating a substrate 10. The chuck plate driving device 13is connected to the chuck plate 12 through a universal shaft 15 to drivethe chuck plate 12 to ascend and descend. Specifically, referring toFIG. 3 , the chuck plate 12 is lifted to the substrate loading/unloadingposition away from the cup-shaped chuck 11 by the chuck plate drivingdevice 13. After the substrate 10 is put into the accommodating space110 by a transfer robot, referring to FIGS. 4 and 5 , the chuck plate 12is driven downward by the chuck plate driving device 13 to abut againstthe backside of the substrate 10 to clamp the substrate 10 between thecup-shaped chuck 11 and the chuck plate 12. Generally, the substrateholding device is connected to the vertical driving device (not shown)through a support plate 17, and the vertical driving device drives thesubstrate 10 clamped by the cup-shaped chuck 11 and the chuck plate 12to ascend or descend. The angle driving device 14 is used to adjust theangle of the substrate 10 clamped by the cup-shaped chuck 11 and thechuck plate 12 during the process of entering the electroplatingsolution, so as to reduce the influence of bubbles in the electroplatingprocess. The rotation driving device 16 is used to drive the substrate10 clamped by the cup-shaped chuck 11 and the chuck plate 12 to rotateduring the electroplating process. It can be understood that when thechuck plate 12 is lifted away from the cup-shaped chuck 11 by the chuckplate driving device 13 to clean the cup-shaped chuck 11, the rotationdriving device 16 can also drive the cup-shaped chuck 11 to rotate.

Referring to FIG. 5 and FIG. 6 , the cup-shaped chuck 11 includes aninner pressure ring 111, a middle frame 112 and an outer pressure ring113, wherein the inner pressure ring 111 is locked on the innerperipheral surface of the middle frame 112, and the outer pressure ring113 is locked on the outer peripheral surface of the middle frame 112.The outer pressure ring 113 is made of insulating material, which candirectly contact the electroplating solution during the electroplatingprocess, and there is no leakage problem. In addition, the outerpressure ring 113 has a certain hardness so as to support othercomponents. Specifically, the outer pressure ring 113 can be made ofPEEK, PVC, PVDF, PFA, CPVC, PE or PC and other materials.

FIG. 9 shows a partial cross-sectional view of the middle frame. Themiddle frame 112 has a side wall 1121, and the upper end of the sidewall 1121 extends radially outward to form a first mounting platform1122. The lower end of the side wall 1121 extends radially inward toform a second mounting platform 1123. The end of the second mountingplatform 1123 extends obliquely inwardly to form the bottom of themiddle frame 112, and the end of the bottom of the middle frame 112extends radially and horizontally inward to form a horizontal supportpart 1124. Wherein the second mounting platform 1123, the bottom of themiddle frame 112 and the horizontal support part 1124 serve as the headof the middle frame 112, and the surface of the head of the middle frame112 is wrapped with a sealing element 114, which will be described indetail hereinafter. Referring to FIGS. 5 and 6 again, a first step 1131is formed on the upper part of the inner side wall of the outer pressurering 113, and a second step 1132 is formed at the lower part of theinner side wall of the outer pressure ring 113. When the middle frame112 is installed in the outer pressure ring 113, the first mountingplatform 1122 of the middle frame 112 is pressed against the first step1131 of the outer pressure ring 113, and the second mounting platform1123 of the middle frame 112 is pressed against the second step 1132 ofthe outer pressure ring 113. As shown in FIG. 9 , several firstpositioning grooves 1125 are spaced apart on the upper surface of thefirst mounting platform 1122 of the middle frame 112. The upper part ofthe inner pressure ring 111 has several first positioning blocks 1111(as shown in FIG. 8 ). When the inner pressure ring 111 is installed inthe middle frame 112, the first positioning blocks 1111 of the innerpressure ring 111 are pressed in the first positioning grooves 1125 ofthe middle frame 112, and the lower part of the inner pressure ring 111is pressed against the second mounting platform 1123 of the middle frame112.

The outer surface of the outer pressure ring 113 has a blocking part forpreventing the process liquid, such as electroplating solution, fromsplashing upward along the outer surface of the outer pressure ring 113while the cup-shaped chuck rotating. The blocking part includes at leastan upper blocking part and/or a lower blocking part. The number of upperblocking parts is one or more than one, and the number of lower blockingparts is one or more than one. The upper blocking part is a downwardannular protrusion formed on the top of the outer pressure ring 113, andthe lower blocking part is an outward annular protrusion formed at themiddle and lower part of the outer pressure ring 113.

The outer pressure ring 113 shown in FIG. 16 (a) has a lower blockingpart 1133. The lower blocking part 1133 is an outward annular protrusionformed at the middle and lower part of the outer pressure ring 113. Thecross-sectional profile of the lower blocking part 1133 can be in anyshape such as circular arc, elliptical arc, parabola or rectangle, etc.which can prevent the liquid from climbing up along the outer surface ofthe outer pressure ring 113 or guiding the liquid to flow downward. InFIG. 16 (a), the lower blocking part 1133 is located at the lowest partof the outer pressure ring 113, that is, flush with the bottom surfaceof the outer pressure ring 113. Of course, it is understood that inother embodiments, the lower blocking part 1133 is higher than thebottom surface of the outer pressure ring 113, and the lower blockingpart 1133 is located at the middle and lower part of the outer pressurering 113, as shown in FIG. 16 (b). When the cup-shaped chuck 11 rotates,the lower blocking part 1133 will increase the resistance of the liquidto climb upward along the outer side wall of the outer pressure ring113. Specifically, when the liquid rotates along with the cup-shapedchuck 11, it will be thrown obliquely downward along the solid linearrow in FIG. 16 (a) into the liquid collection trough arranged in theelectroplating chamber, instead of climbing upwards along the outer sidewall of the outer pressure ring 113 and then throwing out theelectroplating chamber obliquely upwards along the dotted line arrow inFIG. 16 (a), polluting the process environment.

In other embodiments, the outer pressure ring can have two or more lowerblocking parts, which can more effectively prevent the liquid from beingthrown out obliquely upward along the outer side wall of the outerpressure ring when the cup-shaped chuck rotates. FIG. 16 (c) shows thatthe lower part of the outer pressure ring 113 has two lower blockingparts 1133, and the two lower blocking parts 1133 are arranged up anddown along the outer surface of the outer pressure ring 113. Of course,it can be understood that in other embodiments the number of the lowerblocking parts 1133 can be determined according to specific processrequirements, and the number of the lower blocking parts 1133 can alsobe set to three, four or more than four. The outwardly protruding widthsof the two or more lower blocking parts 1133 may be the same ordifferent. For example, the outwardly protruding widths of the two ormore lower blocking parts 1133 may gradually increase from bottom totop, or may decrease from bottom to top.

FIG. 16 (d) shows a schematic view of another outer pressure ring. Theouter pressure ring 113 has an upper blocking part 1134, which is adownward annular protrusion formed on the top of the outer pressure ring113. The upper blocking part 1134 is used to change the flow directionof the liquid, so that when the liquid flowing obliquely upward alongthe outer side wall of the outer pressure ring 113 passes the upperblocking part 1134, the liquid flows obliquely downward along thedownwardly protruding upper blocking part 1134. When the cup-shapedchuck 11 rotates, even if part of the liquid climbs over the lowerblocking part 1133 to the top of the outer pressure ring 113, it will beintercepted by the upper blocking part 1134 formed at the top of theouter pressure ring 113, and under the action of centrifugal force, itwill be thrown obliquely downward into the liquid collection trough setin the electroplating chamber, as shown the solid arrow in FIG. 16 (d),so as to avoid the liquid from splashing out of the electroplatingchamber and polluting the process environment. In the embodiment, theincluded angle θ between the upper blocking part 1134 and the outerperipheral surface of the outer pressure ring 113 is between 80° and120°, preferably 90°.

In another embodiment, the number of the upper blocking parts 1134 mayalso be two or more (not shown in the figure), such as two, three, orfour, and the two or more upper blocking parts 1134 are arrangedradially from inside to outside. The downwardly protruding heights ofthe two or more upper blocking parts 1134 may be the same or different.For example, the downwardly protruding heights of the two or more upperblocking parts 1134 may gradually increase from the inside to theoutside, or may gradually decrease from inside to outside.

In order to reduce the adhesion of the electroplating solution on thesurface of the outer pressure ring 113, the surface of the outerpressure ring 113 is treated with hydrophobicity, such as reducing thesurface roughness of the outer pressure ring 113. In the embodiment, thesurface roughness Ra of the outer pressure ring 113 is less than 10 nm.Preferably, the surface roughness Ra of the outer pressure ring 113 isless than 2 nm; or coating or sputtering a hydrophobic film (such asPTFE coating) on the surface of the outer pressure ring 113; or theouter pressure ring 113 is made of a hydrophobic material, or is mixedwith a hydrophobic material.

The substrate holding device further includes a sealing element 114 anda contact ring 115, wherein the contact ring 115 generally has amounting part and a finger part, and the mounting part is pressedbetween the inner pressure ring 111 and the middle frame 112. Thecontact ring 115 is installed and fixed in the cup-shaped chuck 11. Theend of the finger part is in contact with the edge seed layer of thesubstrate 10 during the electroplating process to conduct electricity tothe substrate. As shown in FIG. 5 and FIG. 6 , the sealing element 114wraps the inner peripheral surface, the bottom and the outer peripheralsurface of the middle frame 112, and the contact ring 115 and thesealing ring 116 are sequentially installed on the sealing element 114,and are pressed on the middle frame 112 by the inner pressure ring 111.The inner space of the cup-shaped chuck 11 is sealed by the sealing ring116, and at the same time, seal is simultaneously formed on the upperand lower sides of the contact ring 115 by the sealing element 114 andthe sealing ring 116, thereby effectively preventing the cleaningsolution or soaking solution from infiltrating into the inside of thecup-shaped chuck 11 during online cleaning or soaking of the cup chuck11 after electroplating, that is, preventing the cleaning solution orsoaking solution from entering between the inner pressure ring 111 andthe middle frame 112. Wherein, the sealing ring 116 can be an O-ringsealing ring.

In the embodiment, as an independent accessory, the sealing element 114can be integrally formed by mold opening or injection molding, and canbe detachably installed with the middle frame 112. Specifically, thesealing element 114 integrally wraps the head of the middle frame 112,and its two ends are locked and fixed on the middle frame 112 by theinner pressure ring 111 and the outer pressure ring 113. When thesealing element 114 has worn out and its sealing performance hasdecreased after multiple uses, the damaged sealing element can beremoved by simply disassembling the cup-shaped chuck 11, and then theequipment can be put back into use by replacing with a new sealingelement, which can reduce the difficulty and cost of replacing thesealing element. In other embodiments, for ensuring the installation ofthe sealing element 114 and the middle frame 112 more firmly, thesealing element 114 may be bonded on the middle frame 112 by anadhesive.

The sealing element 114 can be made of fluorine rubber (such asperfluorinated or fluorine-containing rubber), silicon rubber, etc., andthe hardness range can be between 50 and 90 as measured by a durometer.Specifically, the sealing element 114 can be made of different materialsdepending on the process application. For instance, when electroplatingcopper, semi-fluorinated rubber (such as Viton fluorine rubber) withgood sealing performance and low hardness can be used, while inhigh-temperature electroplating processes like electroplating nickel orgold, perfluorinated rubber can be used. In other embodiments, theadhesion of the electroplated solution to the surface of sealing element114 can be reduced by treating the sealing element 114 to make ithydrophobic. Different methods for hydrophobic treatment of the sealingelement 114 can be employed, such as: 1) using a hydrophobic material(e.g. Teflon) to make the sealing element 114; 2) coating the surface ofthe sealing element 114 with a hydrophobic coating (e.g. Tefloncoating); 3) doping hydrophobic materials (such as doping Teflon) intothe sealing element 114; 4) reducing the surface roughness of thesealing element 114, for example, the surface roughness Ra of thesealing element is less than 10 nm, preferably, less than 2 nm.

FIG. 10 shows a partial cross-sectional view of the sealing element. Thesealing element 114 has an inner end part 1141, an outer end part 1142and a bottom part 1143. Referring to FIG. 6 , the inner end part 1141wraps the inner peripheral surface of the middle frame 112 and ispressed against the upper surface of the second mounting platform 1123of the middle frame 112 by the inner pressure ring 111. The outer endpart 1142 wraps the outer peripheral surface of the middle frame 112 andis locked on the lower surface of the second mounting platform 1123 ofthe middle frame 112 by the second step 1132 of the outer pressure ring113. The bottom part 1143 of the sealing element 114 wraps the bottom ofthe middle frame 112, and bends upward to wrap the horizontal supportpart 1124 of the middle frame 112. Referring to FIG. 10 , the sealingelement 114 protrudes upward at the end of the horizontal support part1124 to form a sealing lip part 1144. The thickness of the sealing lippart 1144 is larger than that of the other parts of the sealing element114. After the substrate 10 is loaded into the cup-shaped chuck 11, thechuck plate 12 presses the backside of the substrate 10 to make the edgeof the substrate 10 be tightly attached to the sealing lip part 1144 toseal the edge and the backside of the substrate 10. In the embodiment,there is no metal support inside the sealing lip part 1144 and thethickness of the sealing lip part 1144 is increased, which caneffectively prolong the service life of the sealing element 114.Besides, since there is no metal support inside the sealing lip part1144, its radial width is only determined by the width of the sealinglip part 1144 itself, which can be designed to be 1 mm or less than 1mm. Preferably, the radial width of the sealing lip part 1144 is 0.4mm-0.8 mm, and more preferably, the radial width of the sealing lip part1144 is 0.8 mm. The sealing lip part 1144 has a radial width of 1 mm orless than 1 mm, which can reduce the edge pressing width when thesealing element 114 is in sealing contact with the substrate 10, and canmeet the requirements of the subsequent narrower and narrower edgeremoval process.

In another embodiment, the sealing element has two or more sealing lipparts. The sealing lip part has a certain elasticity, and can beslightly deformed under the pressure of the chuck plate, so that two ormore sealing lip parts of the sealing element are in sealing contactwith the substrate at the same time to achieve multi-stage sealingbetween the cup-shaped chuck and the substrate and to achieve betteredge sealing effect. Two or more sealing lip parts are distributedradially inward and outward, and the sealing lip parts have the sameheight, or at least two sealing lip parts have a height differencebetween them. Specifically, the height of the sealing lip partsgradually rises radially inward, or gradually decreases radially inward,or is alternately arranged high and low in the radial direction. Inaddition, the total radial width of the two or more sealing lip parts isnot greater than 1 mm, and preferably, the total radial width of the twoor more sealing lip parts is 0.4 mm-0.8 mm.

FIGS. 17 (a) to 17 (c) show a partial schematic view of a sealingelement with two sealing lip parts, which are distributed radiallyinward and outward, respectively, an inner sealing lip part 1144 a andan outer sealing lip part 1144 b. Referring to FIG. 17 (a), the heightsof the inner sealing lip part 1144 a and the outer sealing lip part 1144b are equal, and the height h is about 0.3 mm-0.5 mm. Referring to FIG.17 (b), the height h2 of the inner sealing lip part 1144 a is greaterthan the height h1 of the outer sealing lip part 1144 b, for example,the height h2 of the inner sealing lip part 1144 a is 0.4 mm, and theheight h1 of the outer sealing lip part 1144 b is 0.35 mm. Referring toFIG. 17 (c), the height h2 of the inner sealing lip part 1144 a issmaller than the height h1 of the outer sealing lip part 1144 b, forexample, the height h2 of the inner sealing lip part 1144 a is 0.35 mm,and the height h1 of the outer sealing lip part 1144 b is 0.4 mm.

The sum of the radial widths of the inner sealing lip part 1144 a andthe outer sealing lip part 1144 b in FIG. 17 (a) to FIG. 17 (c) is notgreater than 1 mm, that is, a+b≤1 mm. The radial width a of the innersealing lip part 1144 a and the radial width b of the outer sealing lippart 1144 b may be the same or different, preferably, the radial width aof the inner sealing lip part 1144 a is smaller than the radial width bof the outer sealing lip part 1144 b. Specifically, as shown in FIG.17(c), the radial width b of the outer sealing lip part 1144 b is 0.6mm, and the radial width a of the inner sealing lip part 1144 a is 0.2mm.

In the embodiment, the outer pressure ring 113 is made of insulatingmaterial, specifically, the entire side wall and the bottom of the outerpressure ring 113 are made of insulating material, and the outerpressure ring 113 is locked and sealed with the sealing element 114 fromthe outside, so that the exposed area of the sealing element 114 hassignificantly decreased. Therefore, only the bottom part 1143 is exposedto the electroplating solution during the process, effectively reducingthe risk of damage of the sealing element 114.

Referring to FIG. 10 again, the contact surface of the sealing element114 contacting the outer pressure ring 113 forms several outer sealingprotrusions 1146 for enhancing the sealing between the sealing element114 and the outer pressure ring 113. The contact surface of the sealingelement 114 contacting the middle frame 112 forms several inner sealingprotrusions 1145. When the sealing element 114 is wrapped to the middleframe 112 and locked by the inner pressure ring 111 and the outerpressure ring 112, the inner sealing protrusions 1145 are embedded insealing grooves 1128 disposed on the surface of the middle frame 112. Onthe one hand, the sealing element 114 and the middle frame 112 can betightly assembled, and on the other hand, a multi-stage seal can beformed inside the sealing element 114 to strengthen sealing effectbetween the sealing element 114 and the middle frame 112. When thebottom part 1143 of the sealing element 114 is damaged, the multi-circleinner sealing protrusions 1145 can effectively prevent the infiltratedelectroplating solution from diffusing inside the cup-shaped chuck 11,reducing the corrosion of the electroplating solution to the inside ofthe cup-shaped chuck 11. Therefore, the substrate holding device canresume normal operation by simply replacing the sealing element 114,which is beneficial to reduce the maintenance time and cost of thedevice.

Since it is difficult to achieve complete sealing by pressing two planestogether, the pressing surfaces of the inner pressure ring 111 and theouter pressure ring 113 and the sealing element 114 are provided withseveral bumps (not shown in the figure). Due to the bumps, the innerpressure ring 111 and the outer pressure ring 113 can be completelyattached to the contact surface of the sealing element 114 when locked,thereby improving the sealing performance between the components.

Referring to FIG. 11 , the bottom of the outer pressure ring 113 hasbumps 1137. When the cup-shaped chuck 11 needs to be repaired, the bumps1137 at the bottom of the outer pressure ring 113 can play a supportingrole, so that the sealing element 114 remains suspended and not incontact with the maintenance workbench, thereby avoiding damage to thesealing element 114 or contaminating the surface of the sealing element114. In the embodiment, the height of the bump 1137 at the bottom of theouter pressure ring 113 is about 1 mm.

In the embodiment, the inner pressure ring 111 is made of conductivematerial, usually conductive metal, and the contact ring 115 iselectrically connected to the electroplating power source through theinner pressure ring 111. In another embodiment, the inner pressure ring111 and the middle frame 112 are both made of conductive materials,usually conductive metals, the electroplating power source is directlyconnected to the middle frame 112, and the middle frame 112 iselectrically connected to the contact ring 115 through the innerpressure ring 111. Due to the need of maintain the cup-shaped chuck 11after multiple process cycles, processing liquids such as sulfuric acid,nitric acid, tin-silver deplating solution and various surfactants, etc.are often used. At this time, the inner pressure ring 111 willinevitably contact with the processing liquids. Therefore, the innerpressure ring 111 not only needs to have electrical conductivity, butalso needs to have corrosion resistance. The requirements for materialselection of the inner pressure ring 111 are high, and conductive andcorrosion-resistant metals, such as titanium, titanium alloy, stainlesssteel and other expensive metal materials, need to be used. This willincrease manufacturing and maintenance costs.

Preferably, in other embodiments, the middle frame 112 is made ofconductive material, generally conductive metals, and the contact ring115 is electrically connected to the electroplating power source throughthe middle frame 112. Since the middle frame 112 is sealed by thesealing element 114 and the sealing ring 116, no matter in theelectroplating process or the cleaning of the device, the middle frame112 is not in contact with the process liquids, and there is no risk ofbeing corroded by the process liquids. The material of the middle frame112 only needs to meet the conductivity requirements. Compared with theinner pressure ring 111 as an electrical connection part, therequirements for material selection of the middle frame 112 are reduced,and ordinary conductive metals can be used, which can effectively reducemanufacturing and maintenance costs. And the inner pressure ring 111only needs to be corrosion-resistant, and corrosion-resistant insulatingmaterials can be used instead of being limited to corrosion-resistantconductive materials, thereby expanding the material selection range ofthe inner pressure ring 111 and beneficial for reducing costs andrealizing the online cleaning of the cup-shaped chuck 11. In theembodiment, the inner pressure ring 111 can be made of PVC, PEEK, PTFE,PVDF, PP, etc.

Referring to FIGS. 7 and 8 , the assembly of the cup-shaped chuck 11 isas follows:

Step 1: Wrap the sealing element 114 on the head of the middle frame112, that is, wrap the sealing element 114 on the second mountingplatform 1123, the bottom and the horizontal support part 1124 of themiddle frame 112.

Step 2: Assemble the middle frame 112 wrapped by the sealing element 114into the outer pressure ring 113. The contact surface between the outerpressure ring 113 and the middle frame 112 can be disposed with severalpositioning pieces. As shown in FIG. 8 , the inner side wall of theouter pressure ring 113 has a second positioning groove 1135, and theouter side wall of the middle frame 112 has a second positioning block1120 matching with the second positioning groove 1135.

Step 3: Install the contact ring 115 on the middle frame 112, and thefinger part of the contact ring 115 is used to contact the seed layer onthe edge of the substrate to conduct electricity. For ease of assembly,referring to FIG. 9 , several positioning columns 1129 are provided onthe second mounting platform 1123 of the middle frame 112 so that thecontact ring 115 is mounted on the second mounting platform 1123 of themiddle frame 112 along the positioning columns 1129 and is located onthe sealing element 114.

Step 4: After the contact ring 115 is installed, install the innerpressure ring 111 on the middle frame 112 and press the contact ring115. The first positioning block 1111 formed on the periphery of theinner pressure ring 111 is disposed in the first positioning groove 1125at the top of the middle frame 112, and the sealing ring 116 isinstalled on the lower surface of the inner pressure ring 111. When theinner pressure ring 111 and the middle frame 112 are locked, the sealingring 116 is fixed between the inner pressure ring 111 and the contactring 115.

Step 5: Several screws 117 pass through the first screw holes 1112 onthe inner pressure ring 111 and the second screw holes 1126 on themiddle frame 112 to lock the inner pressure ring 111 on the innerperipheral surface of the middle frame 112, and make the bottom of theinner pressure ring 111 press the sealing ring 116, the contact ring 115and the inner end part 1141 of the sealing element 114 on the secondmounting platform 1123 of the middle frame 112 in sequence from top tobottom. Several screws 118 pass through the third screw hole 1127 on themiddle frame 112 and the fourth screw hole 1136 on the outer pressurering 113 to lock the outer pressure ring 113 on the outer peripheralsurface of the middle frame 112, and press the outer end part 1142 ofthe sealing element 114 between the outer pressure ring 113 and themiddle frame 112.

FIG. 12 and FIG. 13 show perspective views of the chuck plate in theembodiment. The chuck plate 12 includes a base 121, and the base 121 hasa lower surface contacting the substrate 10. Several exhaust grooves 122are formed on the lower surface of the base 121, and exhaust holes 125communicating with the exhaust grooves 122 are opened on the peripheryof the base 121. When the chuck plate 12 is pressed against the backsideof the substrate 10, the pressure on the backside of the substrate 10 isequal to the ambient pressure through the exhaust holes 125 provided onthe periphery of the chuck plate 12, so as to facilitate the separationof the substrate 10 and the chuck plate 12 after the electroplatingprocess is completed, avoiding a slight negative pressure between thechuck plate 12 and the substrate 10 to cause the substrate 10 beingadsorbed on the chuck plate 12, and the unloading operation of thesubstrate 10 is affected.

Referring to FIG. 13 again, the lower surface of the base 121 is furtherprovided with contact parts protruding toward the substrate 10.Specifically, the contact parts can be a plurality of contact bumps 123protruding from the lower surface of the base 121, and a contact ringprotrusion 124 formed on the lower edge of the base 121. As shown inFIG. 14 and FIG. 15 , the protrusion heights of the contact bumps 123and the contact ring protrusion 124 are the same. When the chuck plate12 is in contact with the substrate 10, only the contact bumps 123 andthe contact ring protrusion 124 are in contact with the backside of thesubstrate 10, and the rest of the lower surface of the base 121 is notin contact with the substrate 10. On the one hand, the contact areabetween the chuck plate 12 and the substrate 10 can be reduced, and thescratches and contamination on the backside of the substrate 10 can bereduced. On the other hand, the pressure on the backside of thesubstrate 10 is equal to the ambient pressure to facilitate theseparation of the substrate 10 from the chuck plate 12 when unloading.

As described above, the present invention has been described in detailthrough the description of the above-mentioned embodiments and therelated drawings, so that those skilled in the art can implement itaccordingly. The above-mentioned embodiments are only used to illustratethe present invention, rather than to limit the present invention, andthe scope of rights of the present invention should be defined by theclaims of the present invention. Changes in the number of elementsdescribed herein or substitution of equivalent elements should stillfall within the scope of the present invention.

1. A cup-shaped chuck of a substrate holding device for holding asubstrate, comprising: an inner pressure ring; a middle frame, whereinthe inner pressure ring is locked on an inner peripheral surface of themiddle frame; a sealing element, wherein the sealing element has anouter end part, a bottom part and an inner end part, wherein the outerend part of the sealing element wraps an outer peripheral surface of atleast part of the middle frame, and the bottom part of the sealingelement wraps the bottom of the middle frame and is exposed to theoutside of the cup-shaped chuck, and the inner end part of the sealingelement wraps an inner peripheral surface of at least part of the middleframe, wherein the inner end part of the sealing element is pressedbetween the inner pressure ring and the middle frame by the innerpressure ring; an outer pressure ring, wherein the outer pressure ringis made of insulating material and locked on the outer peripheralsurface of the middle frame, wherein the outer end part of the sealingelement is pressed between the outer pressure ring and the middle framethrough the outer pressure ring; and a contact ring, wherein the contactring is located above the sealing element and pressed between the innerpressure ring and the middle frame, and a sealing ring is disposedbetween the inner pressure ring and the contact ring.
 2. The cup-shapedchuck of a substrate holding device according to claim 1, wherein thebottom of the middle frame forms a horizontal support part radially andhorizontally inward, and the bottom part of the sealing element wrapsthe horizontal support part, wherein the end of the horizontal supportpart protrudes upwards to form a sealing lip part, and the number ofsealing lip part is one or two or more, and the sealing lip part isconfigured for sealing contact with the edge of the substrate.
 3. Thecup-shaped chuck of a substrate holding device according to claim 2,wherein when the number of sealing lip parts is two or more, the heightsof the two or more sealing lip parts are the same.
 4. The cup-shapedchuck of a substrate holding device according to claim 2, wherein whenthe number of sealing lip parts is two or more, there is a heightdifference between at least two of the sealing lip parts.
 5. Thecup-shaped chuck of a substrate holding device according to claim 4,wherein the height of the sealing lip parts gradually increases radiallyinward.
 6. The cup-shaped chuck of a substrate holding device accordingto claim 4, wherein the height of the sealing lip parts graduallydecreases radially inward.
 7. The cup-shaped chuck of a substrateholding device according to claim 4, wherein the heights of the sealinglip parts are alternately arranged high and low in the radial direction.8. The cup-shaped chuck of a substrate holding device according to claim2, wherein when there is one sealing lip part, the radial width of theone sealing lip part is not more than 1 mm, and when there are two ormore sealing lip parts, the total radial width of the two or moresealing lip parts is not more than 1 mm.
 9. The cup-shaped chuck of asubstrate holding device according to claim 8, wherein when there is onesealing lip part, the radial width of the one sealing lip part is 0.4mm-0.8 mm, and when the number of sealing lip parts is two or more, thetotal radial width of the two or more sealing lip parts is 0.4 mm-0.8mm.
 10. The cup-shaped chuck of a substrate holding device according toclaim 1, wherein the sealing element as a separate accessory isdetachable from the middle frame.
 11. The cup-shaped chuck of asubstrate holding device according to claim 10, wherein the sealingelement is bonded to the middle frame by an adhesive.
 12. The cup-shapedchuck of a substrate holding device according to claim 1, whereinseveral inner sealing protrusions are formed on the contact surface ofthe sealing element and the middle frame, and correspondingly, thesurface of the middle frame has several sealing grooves that match theinner sealing protrusions.
 13. The cup-shaped chuck of a substrateholding device according to claim 12, wherein several outer sealingprotrusions are formed on the contact surface of the sealing element andthe outer pressure ring.
 14. The cup-shaped chuck of a substrate holdingdevice according to claim 1, wherein the sealing element hashydrophobicity properties.
 15. The cup-shaped chuck of a substrateholding device according to claim 1, wherein the outer surface of theouter pressure ring has a blocking part.
 16. The cup-shaped chuck of asubstrate holding device according to claim 15, wherein the blockingpart comprises at least an upper blocking part and/or a lower blockingpart, wherein the number of upper blocking parts is one or more, and thenumber of lower blocking parts is one or more, wherein the upperblocking part is a downward annular protrusion formed on the top of theouter pressure ring, and the lower blocking part is an outward annularprotrusion formed at the middle and lower part of the outer pressurering.
 17. The cup-shaped chuck of a substrate holding device accordingto claim 1, wherein the surface of the outer pressure ring hashydrophobicity properties.
 18. The cup-shaped chuck of a substrateholding device according to claim 1, wherein several bumps are formed onthe contact surface of the outer pressure ring and the sealing element,and several bumps are formed on the contact surface of the innerpressure ring and the sealing element.
 19. The cup-shaped chuck of asubstrate holding device according to claim 1, wherein the bottom of theouter pressure ring has several bumps.
 20. The cup-shaped chuck of asubstrate holding device according to claim 1, wherein the material ofthe inner pressure ring is a conductive and corrosion-resistant metal,and the contact ring is electrically connected to an electroplatingpower supply through the inner pressure ring.
 21. The cup-shaped chuckof a substrate holding device according to claim 1, wherein the innerpressure ring is made of insulating material, the middle frame is madeof conductive metal, and the contact ring is electrically connected toan electroplating power supply through the middle frame.
 22. A substrateholding device, comprising: a cup-shaped chuck as claimed in claim 1 forholding a substrate; a chuck plate, wherein the chuck plate pressesagainst the backside of the substrate so that the substrate is inpressing contact with the sealing element of the cup-shaped chuck; achuck plate driving device configured for driving the chuck plateagainst or away from the backside of the substrate; an angle drivingdevice configured for adjusting the angle of the substrate clamped bythe cup-shaped chuck and the chuck plate; a rotation driving deviceconfigured for driving the substrate clamped by the cup-shaped chuck andthe chuck plate to rotate; and a vertical driving device configured fordriving the substrate clamped by the cup-shaped chuck and the chuckplate to ascend or descend.
 23. The substrate holding device accordingto claim 22, wherein the chuck plate comprises a base, the base has alower surface contacting with the backside of the substrate, the lowersurface of the base has several exhaust grooves, and the periphery ofthe base has several exhaust holes communicating with the exhaustgrooves.
 24. The substrate holding device according to claim 23, whereinthe lower surface of the base has contact parts protruding toward thesubstrate, so as to reduce the contact area between the chuck plate andthe substrate.